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3 years ago

Can someone help me please

Physics

2 answers:

Molodets [167]3 years ago

8 0

Meter would be the correct answer.

Evgen [1.6K]3 years ago

5 0

The last one: meter

You might be interested in

A capacitor is charged to a potential difference of 3 volt it delivers 30% store energy to lamp what is the final potential diff

nexus9112 [7]

Answer:

3.98V

Explanation:

Given

Pontential difference V as 3v

Energy delivered is 30%,

Recall that Enery E=1/2cv^2 from this E=V^2(since Current C is not provided we can assume a value 2)

So E=V^2

E=3^2=9

At full charge E=9,30%of 9,0.3*9=2.7 energy in capacitor is 9-2.7=6.3

But E=V^2

✓E=V

✓6.3=3.98V

4 0

3 years ago

A rubber ball of mass 18.5 g is dropped from a height of 1.90 m onto a floor. The velocity of the ball is reversed by the collis

kati45 [8]

Answer:

J=0.211kg.m/s

Explanation:

The impulse-momentum theorem states:

$J=\Delta p\\J=m(v_a-v-b)\\where:\\m=mass\\v_a=velocity\_after\\v_b=velocity\_before$

The velocity before the impact is given by:

$(v_b)^2=2.a.\Delta y\\v_b=\sqrt{2*(9.8m/s^2)1.90m}=6.10m/s(-\hat{j})$

For the velocity after the impact:

$(v_f)^2=(v_a)^2+2.a.\Delta y\\(0)^2=(v_a)^2+2.(-9.8m/s^s).(1.45m)\\\\v_a=\sqrt{2*9.8m/s^2*1.45m}\\v_a=5.33m/s(\hat{j})$

so:

$J=18.5*10^{-3}kg(5.33m/s(\hat{j})-6.10m/s(-\hat{j}))\\\\J=18.5*10^{-3}kg(5.33m/s(\hat{j})+6.10m/s(\hat{j}))\\\\J=0.211kg.m/s$

3 0

3 years ago

The momentum of an object is determined to be 7.2 X 10-3 kg m/s. Express this quantity as provider or use any equivalent unit.

olasank [31]

There could be more than just one answer, since kilograms can be converted to grams, to miligrams, etc.

$7.2\frac{g.m}{s}$

$7200\frac{mg.m}{s}$

Why?

Let's remember some conversion factors to work with kilograms (kg)

$1kg=1000g=1x10^{3}g \\1kg=1,000,000mg=1x10^{6}mg \\1g=1000mg=1x10^{3}mg$

So, we are given the momentum:

$momentum=7.2x10^{-3} \frac{kg.m}{s}$

We can rewrite the units of the momentum (equivalent) as follow:

$momentum=7.2x10^{-3}kg \frac{m}{s}=7.2x10^{3} x10^{-3}g\frac{m}{s}=7.2\frac{g.m}{s}$

and

$momentum=7.2x10^{-3}kg \frac{m}{s}=7.2x10^{3} x10^{6}mg\frac{m}{s}=7.2x10^{3}\frac{mg.m}{s}$

Note: There could be more equivalent units for the momentum, in example, we could work with equivalent units for meters (distance) and seconds (time).

Have a nice day!

8 0

3 years ago

Read 2 more answers

Which best describes the wave seen?

Alona [7]

The wave propagates outward horizontally across the surface of the pond. As you can see from the ripples, the water molecules move up and down, <em>perpendicular to the horizontal movement of the wavefronts</em>.

By definition this is a transverse wave.

7 0

3 years ago

you went to move a 41 kg bookcase to a different place in the living room. if you push with a force of 65 N and the bookcase acc

borishaifa [10]

0.15

Explanation:

Given parameters:

Mass of bookcase = 41kg

Force applied = 65N

Acceleration = 0.12m/s²

Unknown:

Coefficient of kinetic friction between the bookcase and carpet = ?

Solution:

To solve this problem, the forces acting on the bookcase are;

frictional force

net force

applied force

weight

F - f $_{r}$ = ma in the horizontal direction ----- i

F is the applied force

f $_{r}$ is frictional force

m is the mass

a is the acceleration

ma is the net force

In the vertical axis:

R = mg

R is the normal reaction

mg is the weight of the body

f $_{r}$ = μN = μmg , put into equation i

F - μmg = ma

μ is the coefficient of friction

input the variables;

65 - μ(41 x 9.8) = 41 x 0.12

65 - 401.8μ = 4.92

- 401.8μ = 4.92 - 65

- 401.8μ = -60.1

μ = $\frac{60.1}{401.8}$ = 0.15

learn more:

Friction brainly.com/question/6443626

#learnwithBrainly

4 0

3 years ago